Vice President Joe Biden is still contemplating getting into the presidential race, but he's getting a nudge with an ad from a group supporting him. Bernat Armangue/AP hide caption

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At a recent campaign rally in New Hampshire, only a few dozen people showed up to hear former Gov. Martin O'Malley. Many of them were reporters; others were bused in by the candidate's campaign. Tamara Keith/NPR hide caption

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Members of the House of Representatives bow their heads for a prayer as they gather for opening session of the 114th Congress in January. Pablo Martinez Monsivais/AP hide caption

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Hillary Clinton asks protesters opposed to the Keystone XL oil pipeline to stop disrupting her campaign event Friday in Portland, Maine. Robert F. Bukaty/AP hide caption

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A supporter holds up a "Women for H" sign while Hillary Clinton speaks at the New Hampshire Democratic Party Convention last weekend in Manchester. When Clinton ran eight years ago, she downplayed the potential historical significance of her candidacy. This time around, she has made so-called women's issues centerpieces of her campaign. Scott Eisen/Getty Images hide caption

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Supporters of Democratic presidential candidate Hillary Clinton cheer as she arrives at the state's annual Democratic convention Saturday in Manchester, N.H. Jim Cole/AP hide caption

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Democratic presidential candidate Bernie Sanders was tweeting up a storm during Wednesday night's Republican debate. Win McNamee/Getty Images hide caption

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